SAN MARCOS  Ten thousand mornings ago, Greg Evans could not have imagined where Luann would take him.

Evans was 38 years old in 1985, when he began writing and illustrating what has become one of the most successful daily comic strips, named for a never-aging blonde teenager surrounded by a forever young cast of peers and a dog named Puddles.

Now 65, Evans has recently overseen the production of another type of story, dealing with the other end of the life cycle.

It is a musical called “Wrinkles,” written by Evans for an ensemble of older actors and grappling with the aches and pains of an aging generation.

The production debuted in Vista during the spring of 2010, moved to the Welk Theatre last year, and will appear this March in Fallbrook. A casting call went out last week seeking eight actors “with wrinkles” for auditions scheduled Jan. 8-9 at Zion Lutheran Church.

For an artist who has spent 27 years imagining teenage life a few newsprint frames at a time, the show is somewhat of a departure.

“It’s similar in the sense that a comic strip and a stage piece are 100 percent dialogue,” he told me when we sat down in his San Marcos home on Thursday. “All you’re writing is dialogue. Of course, the primary difference is that there’s music involved in a musical.”

Evans wrote all 15 of the songs in “Wrinkles,” and admitted that it took him a while.

“I can play rudimentary piano—just enough to plunk out a melody—then I hire an orchestrator to write the scores,” he said.

Ultimately, the reward of writing for the stage is that Evans gets to witness an audience interacting with his characters. Potentially millions of readers visit “Luann” over breakfast every day, but their smiles are lost to the solitary cartoonist in his den, crafting the story.

“When I write a stage piece, I can sit in the audience and hear a reaction,” he said. “It’s very satisfying when people laugh at a line you’ve written, or applaud a song.”

Evans’ first theatrical piece, “Luann” the musical, debuted in 2006 and has been produced at least a dozen times locally.

He said his purpose with that play was to give teenagers an acting outlet that didn’t require them to portray much older characters.

“I like musicals, and we’ll go and see some high school group trying to do ‘My Fair Lady’ or something—they’ve got gray wigs, and they’re trying to be adults,” Evans told me. “I wrote ‘Luann’ before ‘High School Musical’ came along because there was nothing, really, for teenagers to do.

Similarly, he added, “On the other end of the scale, there’s not much for older actors to do in musical theater. They might play the mom or the dad, but that’s about it.”

Wrinkles have never been a problem for Evans’ leading lady. For the first 12 years, Luann remained 13 years old.

“I aged her to 16 overnight—I had done all of the 13-year-old stuff I could think of—and that’s where she’s been for the last decade or so,” he explained. “But now I’m gearing up for a new phase. I don’t want to reveal too much, but I am thinking along the lines of a progression.

“In the beginning, it was pretty much a gag a day, but after a while you kind of run out of gags to write about the teenage years,” Evans said. “I always wanted to do more serious themes, because being a teenager is serious—these days, especially.”

He writes two months ahead, rendering the story on a large digital screen: “I usually kind of work in batches. It’s all about editing and getting (the word count) down. Instead of having a character say, ‘I don’t understand,’ they say, ‘Huh?’ More room for the pictures. I’ll sit and draw until I’m weary of that, then send it off.

“I just keep doing it,” he added. “Like the guy who rolls the boulder up the mountain endlessly.”

If Luann has kept him young, it has been in the sense that he must maintain a keen awareness of adolescence, always changing, defying definition.

“So I watch the Grammys to see who the current acts are,” Evans said. “I try to keep up on what’s going on with that age group.”

On the other hand, wrinkles were inevitable—hence the latest musical.

“I had to go from the adolescent, teen side of my brain—which is still very active because I’ve never really matured—to my senior side,” he told me. “I just turned 65, so I’m writing from experience about the aches and the pains and the annoyances of old age. It’s hard enough being an adolescent, but I think it’s a lot harder being a senior.”

Directed by Eliane Weidauer, this spring’s production of “Wrinkles” is scheduled for two weekends, March 8-10 and 15-17, at Dominick’s Deli, 1118 N. Main Avenue in Fallbrook. Visit